WASHINGTON -- U.S. President Donald Trump said that Russia did not help him win the 2016 election, speaking as media reports said the Justice Department has convened a grand jury to investigate allegations of Russian efforts to influence the election.

"Most people know there were no Russians in our campaign. We didn't win because of Russia. We won because of you," Trump told a cheering crowd of supporters on a visit to the state of West Virginia late on August 3.

Trump, a Republican, accused Democrats of pushing what he asserted was a "hoax" and "totally made-up Russia story."

The Wall Street Journal and other media outlets reported that Justice Department special counsel Robert Mueller impaneled a grand jury in Washington to investigate whether Trump's campaign colluded with Moscow

Trump said the idea that Russia helped him get elected is "demeaning to all of us and most of all demeaning to our country and demeaning to our constitution."

Trump and other White House officials said they hope the convening of a grand jury will speed up the conclusion of the Russia investigation, which has dogged his presidency since the outset.

"I just hope the final determination is a truly honest one, which is what the millions of people who gave us our big win in November deserve and what all Americans who want a better future want and deserve," Trump said.

The establishment of a grand jury likely will speed the investigation by allowing Mueller, a former FBI director, to subpoena documents and get sworn testimony. But it also could lead to criminal indictments.

Trump's lawyers asserted that the president himself has nothing to fear from the involvement of a grand jury, as there is no indication the president himself is under investigation.

"Former FBI Director Jim Comey said three times the president is not under investigation, and we have no reason to believe that has changed," said White House press secretary Sarah Sanders.

Reuters reported that the grand jury has issued subpoenas in connection with a June 2016 meeting between a group of Russians who had promised damaging information on Trump's Democratic rival Hillary Clinton and Trump's son Donald Jr., his son-in-law Jared Kushner, and former campaign chairman Paul Manafort.

Donald Trump Jr. was told before the meeting that the Russians had promised damaging information on Trump's Democratic rival, Hillary Clinton.

CNN, meanwhile, reported that the investigation was focusing on potential financial crimes.

A grand jury is empowered to determine whether criminal charges should be filed in a matter, and it operates in secrecy. It is made up of ordinary citizens.

It does not necessarily mean criminal charges are imminent or that they will ever be filed, experts say.

Ty Cobb, special counsel to Trump, said he wasn’t aware that Mueller had started using a new grand jury.

“Grand jury matters are typically secret,” Cobb said. “The White House favors anything that accelerates the conclusion of his work fairly...The White House is committed to fully cooperating with Mr. Mueller.”

Mueller was appointed by the Justice Department to investigate Russia’s alleged interference into the 2016 election and any possible links with the Trump campaign or transition team. He is also investigating potential obstruction of justice.

Separate congressional panels are also investigating matters related to allegations that Russia interfered in the election.